background image
Drill holes through the beams in the pattern and sizes that match the holes in the flanges on the
particular bearings you are using.Take care that your bearings will be accurately centered on
each support beam.
Fasten the bearings to each beam with bolts, nuts and lock washers.
You may have to prepare the wood surface of the bearing support beams differently, with
chisels, rasps and files, or use good-sized, sturdy shims, to accommodate bearings with housings
of configurations other than a plain, flat under-surface. THE BEARING HOUSING MUST
Solid steel end pieces fastened to the ends of the pipe shaft provide smooth surfaces to fit into the
Whether fashioned on a lathe or adapted to this application from already-fashioned materials, the
end pieces must be of solid steel and especially important if the bearings you use are not
equipped with set-screws to lock the shaft in place have a smooth cylindrical surface that
makes an interference (tight) fit into each inner bearing surface.
If you fashion the pieces yourself, make the portion that slides into the pipe end the appropriate
diameter to fit into the pipe (you may be able to file the inside surface of the pipe end
somewhat). Incorporate into the shape of the bottom end piece a protruding collar, with an
under-surface milled smooth and flat, that will rest on the lip of the bottom rotor bearing. A
collar fashioned into the top end piece may provide a surer fit into the particular bearing you are
using, or may not be necessary.
The bottom end piece must be long enough to protrude out of the bottom of the bearing.Drill out
and tap the center of this end piece with a left-hand thread to match the thread on the extension
of the shaft of the Mono pump, which rotates counter-clockwise (as viewed from the top).
If you have no access to a lathe, find steel bar with a diameter that will fit tightly into each
bearing that you have chosen to use.
Depending on the bearing sizes and the actual inside diameter of the pipe shaft you are using,
either grind down or build up (with a sleeve) at least a 3 or 4" length of each end piece to fit
snugly into the end of the pipe shaft. If the bottom bearing you are using does not have set-
screws to lock the pipe shaft positively in place, use a locking collar that can be purchased with
some bearings around the protruding shaft of the bottom end piece, to rest on top of the lip of
the bottom bearing. A Seal Master MSFT16-T (or MSFT 16-TC with a moisture-proof seal) is
sold with a locking collar for US$13.40 (may be more now). You can do without a collar on
the top end piece; take care in final assembly to account in your measurements for a space
between the lower lip of the top bearing and the unmilled end of the pipe shaft.